Mechanic's lien

A mechanic's lien is a security interest in the title to property for the benefit of those who have supplied labor or materials that improve the property. The lien exists for both real property and personal property. In the realm of real property, it is called by various names, including, generically, construction lien. It is also called a materialman's lien or supplier's lien when referring to those supplying materials, a laborer's lien when referring to those supplying labor, and a design professional's lien when referring to architects or designers who contribute to a work of improvement. In the realm of personal property, it is also called an artisan's lien. The term "lien" comes from a French root, with a meaning similar to ; it is related to "liaison". Mechanic's liens on property in the United States date from the 18th century.

Mechanic's liens in their modern form were first conceived by Thomas Jefferson, to encourage construction in the new capital city of Washington. They were established by the Maryland General Assembly, of which the city of Washington was then a part. However, it is not likely that Jefferson single-handedly dreamed up the idea.

At the time Jefferson promoted the law, a lien-like privilege already existed in civil law countries like France, the Dutch Republic and Spain, with some laws even tracing their roots to the Roman Empire. And since control of Louisiana had passed between the French and Spaniards, and had largely adopted the French Napoleonic Code, there was a similar privilege concept in that territory.

It seems highly likely that the legislators working on the first U.S. Mechanic Lien laws had knowledge of, and referenced these civil law concepts. Nevertheless, the United States version was original, as it gave builders a more robust right into the land itself (versus just the improvement’s value).

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